Metallurgical furnace



y 9 G. L. DANFORTH, JR 1,769,213

- METALLURGICAL FURNACE Filed April 6, 1922 4 Sheets-Sheet 1 July 1, 1930. G. L. DANFORTH, JR METALLURGICAL FURNACE 4 Sheets-Sheet 2 Filed pril 6. 1922 7 www July 1, 1930- G. L. DANFORTH. JR

METALLURG I CAL FURNACE Filed April 6, 1922 4 Sheets-Sheet 4 Patented July]. 1, 1 930 UNITED 1 srArss GEORGE 1.. nAnronrn, ar or CHICAGO, rumors, Assrenoa, BY mnsnn Assren- ATENT MENTS, TO OPEN HEARTH COMBUSTION COMPANY, OF CHICAGO, ILLINOIS,

'ronArron or DELAWARE rinrALLuneIcAr. FURNACE -App]1cation filed April 1922. Serial no. 549,974.

This invention relates to a new and improved metallurgical furnace and more particularly to an arrangement of ports and passages for the introduction of air and fuel and for the carrying away of the products of com bustion in such furnaces.

My invention is particularly applicable to an open hearth furnace and is shown in connection'with a furnace of that type. As is well known in the art, open hearth furnaces are provided with two similar ends and are I reversed'in their operation so that each" end serves alternately for the introduction of the air and fuel and for the carrying away ofthe' products of combustion. Since-the products "of combustion considerably exceed in volume the incoming air and gas, the ports of neces sity are largely dependent in design and size upon the re uirement that they properly conduct away t e products of combustion. In

order that the furnace may operate with efliciency, the incoming air and gas must be properly controlled and adequately intermingled to produce a relatively short, hot flame. It is also necessary to control this flame and to properly direct it against the bath of metal in the furnace chamber.

' Qertain furnace constructions have been designed in' the endeavor to avoid these difiiculties, such, for example, as that disclosed In the patent to McKune No. 1,339,855, issued May 11, 1920, in which are providedfadditional passages for carrying off the products of combustion,-these passages being closed upon the incoming end of the furnace.

7 It is an object of the present invention to provide a furnace having additional ports and passages for carrying ofi the products 0 combustion, such passages being controlled so and being connected withthe incoming passages.

][t is an additional object to provide a construction in which air and fuel passages lead to a combined air and fuel port and inwhich the air passages are connected additional Figu passages which serve to carry off the 'products ofc'ombustion.

It is a further object to provide a construct1on of this character in which the air stream enters the combined air and fuel port in the according to my invention;

A Figure 2 is a horizontal section of Figure 1 taken on line 2-2 of Figure 1;

' Figure '3' is a half transverse. vertical section taken on line 3-3 of Figure 1 and show-' ing the damper in the raised position;

showing the damper in the lowered position;

v Figure 5 is a. view similar to-Figure 1 showing a modified form of construction;

' Figure 6 is a horizontal section taken on line 6--6 of Figure 5;

re 7 is a view similar to Figure 1, showing a further modified form;

Figure 8 1s a horizontal" section taken on line 8-+8 of Figure 7;

Fi ure 4 is a view similar to Figure 3 but Figure 9 is a vertical, transverse section taken on line 99' of Figure 7 Figure 10 is' a view similar to Figure 1, showing a stillfurther modified form;

Figure 11 is a horizontal sectiontaken on line 1111 of Figure 10; and

Figure 12 is a horizontal section taken on f line 12-42 of Figure 10.

Referring now to the form of construction shown in Figures 1 to 4, the furnace comprises the furnace chamber 16 to which leads the combined air and fuel port 17. The gas port 18efxtends into the rear of'the' com; bined port-I The gas uptake 19 leads to'the gas port 18. Downtakes 20 and 21 communicate with the furnace through ports 22 and 23, respectively.

As best shown in Figures 3 and 4, the downtakes and 21 are each controlled by a damper 24 which is fixed on a pivot 25. As shown in Figure 3, the damper, when in its raised position, fits into a recess 26 formed in the lateral wall 27 of the furnace. The bypass passages 28 and 29 lead from the downtakes 20 and 21, respectively, to the air uptakes 30 and 31. These uptakes meet at 32 above the gas port 18 and lead into the combined air and fuel port 17.

Referring now to the form of construction shown in Figures 5 and 6, the combined air and fuel port 35 leads to the furnace chamber 36. The fuel uptake 37 leads from the slag pocket 38 to the combined port 35. The downtakes 39 lead from the discharge ports 40 to the slag pocket 41. The transverse passages 42 connect the downtakes'with the air uptake 43 which latter communicates with the rear of the combined air and fuel port 35. The downtakes 39 are controlled by dampers 44 at points above the entrance of the passages 42 into the downtakes.

Referring next to the form of construction shown in Figures 7, 8 and 9, the combined air and fuel port 48 leads to the furnace chamber 49. The fuel uptake 50 leads into the combined port and its lower end communicates with the slag pocket 51. The air uptake 52 leads from slag pocket 53 into the rear of the combined air and fuel port 48. The discharge downtakes 54 communicate with the furnace chamber 49 through ports 55. These downtakes are controlled by water-cooled mushroom valves 56 which rest on seats 57 and are operated by cables 58 passing over pulleys 59. The by-pass passages 60 and 62 connect the downtakes 54 with the air uptake 52, these passages entering the downtakes below the mushroom valves.

In the form of construction shown in Figures 10 to 12, the combined air and fuel port 65 enters the furnace chamber 66. The gas uptake 67 leads from the slag pocket 68 to the forward portion of the port 65. As shown in Figure 12, the downtakes 69 communicate with the furnace chamber through ports 70. As shown in Figure 11, these downtakes are controlled by dampers 76 and below the dampers are connected by by-pas sages 71 to the air uptake 72. This air uptake .7 2 leads into the rear end of the combinedair and fuel port. In the form shown, an auxiliary passage 73 is providedconnecting the air uptake with the forward portion of the combined port immediately in rear of the junction of the fuel uptake with the port. This passage 73 is controlled by a swinging damper 74 which is pivoted at its edge toward the furnace end.

In the operation of the form of construction shown in Figure 1, upon the incoming end of the furnace, both dampers 24 are lowered to the position in which the damper is shown in Figure 4. Incoming air comes through re'generators (not shown) and passes through the by-pass passages 28 and 29 to the air uptakes 30 and 31. The air thus enters the combined port 17 above and on both sides of the gas which enters through the port 18, and the air and gas are properly intermingled in the combined port. Upon the outgoing end, the dampers 24 are raised to the position shown in Figure 3. The outgoing products of combustion will largely pass through the lateral ports 22 and 23 to the downtakes 20 and 21 and thence to the regenerators. Some portion of the gases will pass in through the combined port and down through the fuel uptake. Some small portion may pass through the air uptake and bypass passages.

In the operation of the form of construc tion shown in Figures 5 and 6, upon the incoming end, the gas is introduced into the combined port 35 through the gas uptake 37. The dampers 44 are in the closed position and the air passing up the downtakes 39 is directed by the dampers through the lateral connecting passages 42 and thence to the air uptake 43. From the air uptake, the air passes directly into the rear of the combined port and in the forward portion of the port, it is properly intermingled with the gas. Upon the outgoing end, the dampers 44 are withdrawn and the greater portion of the gases of combustion pass out through ports 40 directly to the upper end of the downtakes 39. A portion of these gases will enter the combined port 35 and pass down through the gas uptake 37. Some proportion of them may pass through the rear of the port 35 and through the passages 42 to the downtakes.

In the form of construction shown in Figures 7 to 9, the gas is introduced into the combined port through the gas uptake 50. The air comes up the downtakes54 as well as the uptakes 52. The mushroom valves are closed down upon their seats and that portion of the air coming up downtakes 54 is directed through lateral passages 60 and 62 to the passage 52. From uptake 52 the air passes into the rear of the combined port and there joins with the gas to produce the proper flame in the furnace chamber. Upon the outgoing end, the mushroom valves 56 are raised and the greater portion of the products of combustion passes out through the ports 55 and down the downtakes 54. A portion'of the products of combustion will enter the combined port and of such portion part will go down the gas uptake and part .down the air uptake 52.

In the operation of the form of construction shown in Figures 10 to 12, the gas is introduced into the forward portion of the combined port 65 by the gas uptake 67. The

upper portion of the rear wall of the uptake 5 comes up the downtakes 69 and is directed b .dampers into the lateral passages 71 whic lead it to the'air uptake '72. From the-air uptake the air passes into the rear of the combined port 65. If desired, a portion ofthe air may be sent through the supplemental passage 73. If it is not desired to send any air through the passage 73, the damper 7 4 is swung down to block this passage. Upon the outgoing end, the major portion of the products of combustion will pass through the lateral ports r to the downtakes 69 and thence to suitable regenerators. Some portion of the products of combustion will enter the combined port 65 and of such portion part will pass down the gas uptake and part down the air uptake.

It is to be understood that in all of the forms shown, suitable regenerative chambers are provided, such chambers being well known in the art and forming no part of the present invention. In all the forms shown, the additional passages for the products of combustion are controlled by dampers and all such passages are connected by passages to air uptakes. These latter passages all enter the downtakes at points below the dampers. While mechanical dampers are shown,- the dampers may consist of etsof high velocity air, steam or the like, if desired. In each construction the gas is introduced into the combined fuel port in advance of the air. It is obvious, however, that the air may be introduced in advance of the gas by means of similar passages if desired.

All forms of construction shown and described herein are adapted for use with producer gas or similar fuels while the particular construction shown in the prior patent to McKune, to which reference has been made is adapted for use with coke oven or natural 1 gas or similar fuels and is not adapted for use with producer gas.

It is to be understood that the various forms shown are illustrative only and I reserve the right to make any such modifications as come within the spirit and scope of the appended claims. Y

I claim;

1. In an open hearth furnace, combined ports for incoming air and fuel, air and fuel passages, and means adapted to selectively interrupt communication between the outgoing' passages and the furnace chamber.

3. In an open hearth furnace, combined ports for incoming air and fuel, air and fuel passages leading to said ports, ports for the products of combustion, passages leading to "said ports, by-pass passages connecting the incoming air passages with said outgoing passages, and means adapted to selectively interrupt communication between the outgoing passages and the furnace chamber, said means being located intermediatethe outgoing ports and the junctionof the by-pass passages with the outgoin passages.

4. In an open hearth ED115106, combined ports for incoming air and fuel, air and fuel passages leading to said ports, ports for the productsof combustion, passages leading to said ports, by-pass passages connecting the passa es, and mechanically operated dampers a apted to selectively interrupt communication between the outgoing passages and the furnacechamber.

5. In an open hearth furnace, combined ports for .incoming air and fuel, air and fuel passages leading to said. ports, the fuel passage entering the combined port in advance of the entrance therein of the air .passage, ports for the products of combustion, passages leading to said ports and by-pass passages connecting the incoming. air passages with said outgoing passages.

6. In an open hearth furnace, combined ports for the incoming air and fuel, a fuel uptake leading to each combined port, ports for the productsof combustion leading to downtakes located laterally of the-fuel uptake, an air uptake entering the combined" incoming air passages with "said outgoing.

uptake leading to each combined port, ports Y for theproducts of combustion leading to downtakes located laterally of the fuel uptake, an air uptake entering the combined port, passa es connecting said air uptake to the downta e passages, and means'adapted to selectively lnterrupt communication begween said downtakes and the furnace chamer I 8; an ports for the incoming air and fuel, a fuel uptake leading to each combined port, ports for the products of combustion leading to downtakes located laterally of the fuel up- "take,.,an air uptake entering thecombi-ned" open hearth furnace; -.co1i1bined Passages connecting said; ir uptake" at r the downtake passages, and mean adaptai to selectively lnterrupt communication;

tween said downtakes and the furnace chame her, said means being located intermediate.

the outgoing ports and the junction of the connecting passages with the downtakes.

9. In a open hearth furnace, combined ports for the incoming air and fuel, a fuel 5 uptake leading to each combined port, ports for the products of combustion leading to downtakes located laterally of the fuel uptake, an air uptake entering the combined ort in the rear of the entrance therein of the eluptake, and passages connecting said air uptake to the downtake passages Si ned at Chicago, Illinois, this 31st day of arch, 1922. 1

GEORGE L. DANFORTH, JR. 

